JOHN VON RADOWITZ

The pathway to obesity can be identified in babies as young as six months of age, scientists have shown.

Researchers used simple Body Mass Index (BMI) measurements to single out infants destined to struggle with weight in later life.

Study leader Dr Allison Smego, from Cincinnati Children’s Hospital in the US, said: “These children have a high lifetime risk for persistent obesity and metabolic disease and should be monitored closely at a very young age.”

BMI is a system of relating height and weight and expressed as kilograms per metres squared. In adults, a BMI of 30kg/m2 or above is classified as “obese”.

Dr Smego’s team looked at several groups of lean and overweight children under the age of six. They included severely obese children referred to Cincinnati Children’s Hospital for specialised care.

The researchers compared 783 lean and 480 severely obese children, selected on the basis of their BMI readings between the ages of two and six.

Growth and weight records showed that the BMI trajectories of children who were severely obese by the age of six began to differ from that of normal weight children at about four months of age.

“BMI at six, 12 or 18 months of age ... can accurately predict children at risk for early childhood obesity,” said Dr Smego, whose findings were presented at a meeting of the Endocrine Society in Boston, US.

She added: “It’s not currently recommended to measure BMI in children under the age of two, but we say it should be because we now know it predicts obesity risk later.

“Paediatricians can identify high-risk infants with BMI above the 85th percentile (top 15 per cent) and focus additional counselling and education regarding healthy lifestyles toward the families of these children.”

A study published in The Lancet journal on Thursday predicted that – if current trends continue – more than a fifth of people in the world will be obese by 2025.

The research, led by a team from Imperial College London, showed that between 1975 and 2014 the global number of obese individuals had soared from 105 million to 641 million.